Er as well as the BGH poly A signal. (B) HEK293T cells have been transfected with SIV pDNAs expressing p27CE1 (lane 1), p27CE2 (lane two), p57Gag (lane three), Gag-Pro (lane 4). Lane five consists of a sample from mocktransfected cells. Proteins from the cell-associated (major panel: 1/100 from the sample) and extracellular (bottom panel: 1/250 in the sample) were analyzed. Western immunoblots wer